The monarchs will need milkweed when they arrive in the north.
Milkweed and wildflower nectar are the monarchs primary source of food.
They will be very hungry from their long journey. They also need this food
for the poison, to protect them from their predtors. Milkweed is also
needed for the females to lay their eggs. The monarchs will also need rest
because they use most of their energy during their long flight. Finally
they will need warm weather in order to stay alive. Not only will warmer
temperatures keep them warm, but it will enable them to fly higher in the
sky, away from predators on the ground.